Paper.



E. THOMAS.

PAPER.

APPLICATION FILED DEC-24,1912.

W [AIM/Wm m 4 INVENTOR: WITNESSES= a TEN: O F

EDWARD THOMAS, 015 NEW YORK, N. Y.

rerun.

Specification of Letters Patent.

Patented Get. 23, 1917.

' Application filed December 24, 1912. Serial No. 738,412.

To all wltom it may concern: 1

strength which is either porous or easily rendered porous in spots. For this purpose I take a strong porous paper and size it with a substance which will bind the fibers together and yet not destroy the porosity, or else I size it with a substance which. is easily softened, and easily displaced when softened. I preferably use Japanese paper known as Yoshino paper. This I may pass through an aqueous solution of shellac, drawing it over a doctor bar to remove any excess of solution and when dried this produces a paper several times as strong as the original paper, yet the porosity of the paper is not sensibly diminished.

I make my solution of shellac by making a concentrated solution of borax in water and then 'in this I dissolve all the gum orange shellac possible. thus obtained shows a tendency to obstruct the pores of the paper I dilute it. I have found that such a solution made at a temperature of 75 F. should be diluted with toward a third ,its volume of pure water.

This paper forms an excellent basis for making wax stencil paper of the type used in mimeographs, duplicators, etc. If waxed with the composition disclosed in my copending application No. 707 ,254, filed July 2, 1912, for wax stencil paper, I find that though the shellacked paper draws the wax through it much more easily than the wax strikes through plain paper, yet the wax does not dissolve the shellac enough to weaken the paper if it dissolves it at all. Such paper is strong, flexible and makes excellent stencils on a typewriter especially when backed with a hard sheet. I

The object of using such a shellac solution seems to be that it has almost no body and so it dries on the fibers themselves and If the solution does not form a film between them. I believe other substances such as casein glue in thin solution would have the same effect.

In the accompanying drawing, 7 Figure 1 is a View of a stencil sheet, with the coating partly removed; and

Fig. 2 is a' cross-section through same, both figures being greatly exaggerated in places. 7

Yoshino paper 1, which is composed of very strong fibers forming an open felt, is diagrammatically shown at the upper left- 1 hand corner of Fig. 1. The fibers are shown therein far more widely spaced than is usual in such paper. A little removed from the corner is shown. a part of the paper 2,

which has been treated with, shellac in the manner .described,,b,ut not coated with wax.

' It will beobserved that the coating of shel- 1210 is shown to be almost exclusively deposited at the points where the fibers cross each other as at 3, with the result that the porosity of the paper is scarcely effected at all. The paper, as illustrated in Fig, 1, has the shellac therein far more prominent than it is relatively in the paper as actually made.- The remainder 4 of thesheet shown in Fig. 1 is coated with wax. In the cross- .section shown in Fig. 2, the surface of wax is shown at each side at 5, with the shellacked paper 2 in the center, shown diagrammatically made as it is in Fig. 1.

I also have made paper by drawing Yoshino paper through orange shellac varnish which has been modified.

by allowing it to stand uncovered. before drawing the paper through it. The shellac varnish I used is the heavy orange shellac of commerce, supposed to be made by cutting three and a half pounds of shellac with a gallon of alcohol.

I have also made paper by making a varnish of shellac in some solvent which also dissolves aluminum oleate, and then drawing the paper through the solution. Such a solvent is amyl acetate. I have found that the solution must contain less than 10% of oleate of alumina, and preferably a good I I- have obtained the best results when about 30% of ,c'astor oil has been added to the shellac varnish and then the varnish has been thickened deal less than this or the solution will thicken without evaporation. I believe that a good dealless than 5% of oleate of alumina and about 20% of shellac will be found est.

Paper should be coated with these varnishes by drawing it through them and then over a doctor bar. O leate of alumina is a softener which is almost unafl'ected by temperature changes.

Paper coated with these varnishes does not need to be waxed but may be softened so as to write stencils on it by moistening with a solution of borax in water. Said solution may be nearly concentrated and should be applied without much rubbing.

While I have described in detail certain embodiments of my invention, it'will be obvious to those skilled in the art that many improvements and modifications may be made therein, and ll have set forth details only to enable those skilled in the art to understand how my invention may be used in certain of its preferred forms.

What therefore I claim as my invention is:

1. A porous paper comprising a sizing deposited on its fibers without materially altering its porosity.

QQA porous paper comprising a deposit of shellac on its fibers without materially altering its porosity.

3. A paper comprising a' porous base and v a sizing on said base,- such that the paper Where sized is still almost equally porous,

and a coating of Wax covering the paper and making the whole non-porous except where the wax may be removed.

4. A waxed paper comprising a porous base, a deposit of shellac on said base, and a,

wax on said shellacked paper.

5. A paper of open mesh strengthened with shellacand having a continuous wax coating above the shellac.

6. The combination with an open meshed paper having a continuous waX- coating thereon, of shellac also deposited thereon so as to act as a strengthener of the paper.

7. The combination with Yoshino paper, of a size thereon strengthening it without altering its porosity.

8. The combination with Yoshino paper, of a size thereon strengthening it without altering its porosity, and an easily removable continuous coating thereon.

9. The combination with Yoshino paper, of a size thereon strengthening it without altering its porosity, and a waxy coating EDWARD THOMAS.

Witnesses 1F. GRANVILLE MlUNSON, GILBERT W. ROBERTS. 

